Machine for making laminated paper tubes



y 8, 1952 R. H. VON LIEDTKE 2,602,382

MACHINE FOR MAKING LAMINATED PAPER TUBES Filed Sept. 4, 1945 3 Sheets-Sheet l 1N VEN TOR. fwa/M/MM/m/m A 7 O/PM FY.

I R NE F 'M ON IN L G LAMIINEDTKE PAP July 8, 1952 R. H. VON LIEDTKE MACHINE FOR MAKING LAMINATED PAPER TUBES Filed Sept. 4, 1945 3 Sheets-Sheet 5 L .2 x R/ mm M MM Wm Nm 7 M fl Y B [a A| J a Patented July 8, 19 52 UNITED STATES PATENT "OFFICE V MACHINE FOR/MAKING LAMINATED TUBES Rudolph H. von Liedtke, Chicago, 'Ill., assignor, by mesne .assignments, 'to .McGraw Electric Company, a corporation of'D'elaware Application September 4, 1945,"Serial No. 614,356

This invention relates to a machine for making laminated paper tubes from paper pulp or other fibrous materials.

In making tubes from paper pulp or other fibrous'materials it has been the practice heretofore to form the tube by winding a sheet of paper pulp on a mandrel, removing the tube from the mandrel, drying the tube, and impregnating the tube with a nonabsorbent. waterproof, binding agent. In the prior process it was found that the layers did not always adhere and that frequently air of water pockets or voids were 'formed between successive layers, bogh of these defects materially weakening the This invention is designed to overcome the above noted defects and objects of this invention are to provide a machine for making a tube in which provision is made for securely attaching succeeding layers to preceding layers at a multitude of spaced points to produce the effect of stitching successive layers together so as to provide a tube in which venting of the air 'or water pockets is provided and also one in which the layers are securely and firmly at- 1 Claim. (01. 92 -66) taohed one to the other during the making of shown in the accompanying drawings in which:

Figure 1 is a transverse sectional view through the machine, such'view corresponding 'to a section on the line |-l of Figure 2.

Figure 2 is .a side elevation partly in section and partly broken away of .a portion of the machine. I Figure 3 is a fragmentary view showing the manner in which the stitching roller ordrum operates. v

Figure 4 is a view showing a further form of stitching drum. V Figure 5 is a view of a fragment of a tube with a temporary sealing coating on the outer surface of the tube.

Figure 6 is a fragmentary view of ta portion of the impregnated tube.

Figure 7 is a fragmentary view of a portion of a tube showing a void in the tube.

. 2 Figure 8 is a diagrammatic view showing the paper pulpbeing wound on a mandrel.

Figure 9 is a perspective view of the tube as it comes from thetube forming machine.

Figure 10 is a view of a fragment of the tube, such view being in section and partly broken away. a

Figure 11 is a view of the impregnating. tank. Figure 12 is a fragmentaryview of a portion of the tube, such view being partly in section showing one stage in the process of impregnation.

Figure 13 is a view corresponding to Figure 12 showing a further step in the process of impregnation.

Figure 14 is a view corresponding to Figure 12 showing the finished impregnated tube.

The machine is adapted to follow the ordinary process of winding paper pulp in succes-r sive layers to form the paper tube and, in addition to this, provides means for stitching or securely attaching successive layers to preceding layers at a multitude of spaced points.

The machine chosen for illustration comprises a tank I which is adapted to receiv'epaper pulp 2. The paper pulp is 'fed to the tank I in any suitable manner, not shown, and is maintained at the'proper level. It may have iron-free alum added to the bath in accordance with the usual practice'if so desired. A hollow drum or roller 3 is provided and has a perforated peripheral portion surrounds bya screen 4. A partial vacuum is produced within the drum 3 and the paper pulp is sucked up against the drum, the drum being rotated in the direction indicated. This paper pulp passes to an intermediate hollow perforated drum 5 which is surrounded with a layer of felt or suitable material 6 and preferably a higher vacuum is produced in the drum 5. The drum 5 receives the layer of paper pulp from the drum '3 and delivers it to a mandrel 1 on which the tube is wound. The machine is provided with a plurality of mandrels '1 carried in suitable revolubly mounted heads 8 which are slotted as indicated at '9 to receive the reduced trunnions IU of the mandrels. The heads 8 and the mandrelsl are adapted to be regularly indexed to bring successive mandrels into operative position and locking means are'provided for temporarily locking the heads and the mandrels in their successive positions.

The locking means may take any suitable form. For instance, it may consist of a lever ll pivotally mounted as indicated at l2 and provided with a foot or locking means (3 adapted to enter the notches cor slots .9 in. one of the heads indexed as the tubes are completed. Guard rails l5 extend part-way around the heads and prevent escape of the trunnions ID from the slots 9 exceptin one position, for instance, the lefthand position of Figure 1, to allowthe removal of a wound tube from a mandrel. The machine may be driven in any suitable manner. stance, in accordance with the usual practice the drum 5 may be driven by means,nct shown, and may thus drive the lower drum 3 and the mandrel? on which the tube is being wound.

For in-" The machine thus described is the conventional type of tube forming machine-and theusual accessories are, of course, provided in accordance with the usual practice.

The machine is provided with a stitching roller [6 which is journaled at opposite ends in the bell crank levers l1 pivotally mounted as indicated at l8 upon floating pivoted heads l9 loosely carried by the central shaft 20, which central shaft is rigid with the end heads 8. The upper portions of the bell crank levers I! are joined by means of a transverse bar 2|. This transverse bar constitutes means whereby pressure may be applied between the stitching roller 16 and the tube. The operator, in the instance chosen for illustration, presses against the transverse bar 2! and thus forces the stitching drum or roller it against the tube while it is being wound. Any other suitable means may be provided for accomplishing the same result, the means chosen being merely one of many possible ways of accomplishing the desired result.- The stitching roller 1 understood'thata multitude of indentations or stitch points are provided. If desired, the pres sure exerted on the stitching roller I6 may be sufiicient to cause the prongs 22 to actually puncture one or more layers.

The stitching roller may take other forms. For example, as shown in Figure 4 the stitching roller It may have angular or bent points 22' if desired. It will be seen that by the method hereinabove described the successive layers are firmly united with preceding layers by forcinga portion of one or more layers into or through portions of preceding layers. This is illustrated'more clearly in Figure 5 in which the-completely wound tube is indicated by the reference character 23 and the.

entrapped air between the -oncoming sheet of paper pulp 26, see Figure 8, and the partially '30, see Figure 11.

formed tube at the point indicated by the reference character 21.

' It is to be noted also that wherever any of the stitching points reaches one of the voids that the air entrapped in the void is allowed to escape and the formation of voids very muchreduced if not substantially prevented}. It is tobe noted that the stitching roller is a relatively lon roller and is provided witha multitude of spaced points or pins as shown in Figure 2. The pressure exerted between the stitching roller [6 and the tube while it is being wound is distributed over a multitude of points and. consequently there is no danger of one point digging into the partially formed tube to an indexed in the direction shown in :Figure v1 and it will be seen that the stitching roller Hivis pushed upwardly during this operation and allows free passage of the completed tube. It drops back into position to engage the tube being formedon the succeeding mandrel and again pressure is applied through the medium of the pressure bar2l or in any other suitable manner.-

by Rudolph H. von Liedtke, now; Patent Number In following the method set forth in the copending application, hereinabove noted, spray means such as indicated by the. reference character 28' in Figure l isprovided for spraying a temporary sealing coating 'ofsize 29, see Figure 12, on the outer side of the tube. This spraying takes place during the winding of the last few convolutions of the tube and any suitable sizing material may be employed provided it has the characteristics of sealing the surface of the tube and also of disintegrating or disappearing or be-' coming ineffective for a certain temperature range of the pitch, thus allowing the coating to either disintegrate or disappear at a certain stage in the process of impregnating the tube. A suitable size is silic-ate of soda which is sprayed on the tube as described. It may be sprayed either on the first few convolutions to thus seal the inner surface of the tube or may be sprayed on the outer convolutions of the tube to seal the outer surface of the tube The tube: with the sealing coating thereon isthcrcughly dried and after drying is placed in the impregnating tank This impregnating tank is supplied with heatedpitch through the supply pipe 3i at its lower portion and the pitch is pumped from the upper portion of the tank through the outlet pipe 32 by means of a pump 33 or in any other suitable manner so that heated pitch is circulated through the tank; The tank is provided with a lower steam jacket 35., The

upper portion of the tank is connected to a threeway valve 35 which is adapted to connect the tankwith a suitable source ofva-cuum-by means of the vacuum pipe- 36 'or with the outside'air or air under pressure by means of the air pipe 31 depending upon the setting of the valve.

When the tubes are positioned within the tank the pitch is caused to circulate and the three-way valve 35 is turned so as to produce a vacuum in the upper portion of the tank. This lowers the temperature of the pitch and prevents destruction of the sealing coating. The air, it will be noted, which is entrapped within the wall of the tube flows radially inwardly in one direction only away from the sealing coating. After a suitable interval of time the three-way valve is turned to admit air to the upper portion of the tank and to relieve the vacuum. The pitch now flows radially from the uncoated inner side of the tube towards the coated side of the tube and thus uniformly impregnates the wall of the tube. When the vacuum is relieved the temperature of the pitch rises and the sizing coating or sealing coating 29 disappears or is substantially destroyed after a predetermined interval of time and allows the pitch free access to the outer surface of the tube. In this way there is no chance of air being trapped within the wall of the tube which would prevent even and complete penetration of the pitch. This process of impregnation is set forth in greater detail in the copending application hereinabove noted. The sealing coating is indicated in Figures and 12 and a fragment of the finished tube is indicated in Figures 6 and 14. For the sake of simplicity, it is to be noted that the stitching points have been omitted in Figures '7, 12, 13, and 14.

The stitching of the tube binds successive layers together and relieves the voids. The result of this is that the successive layers of the tube are very firmly bound together not only by the binding action of the pitch which is a waterproof, binding, impregnating agent, but also due to the stitching of the successive layers.

The stitching occurs at a multitude of closely spaced points, a few only of which have been shown in Figures 5 and 6.

It will be seen that a novel and simple form 7 of machine has been provided by this invention which is arranged to stitch successive layers to preceding layers of the paper pulp tube while the layer of paper pulp is being wound to produce the tube.

It will be seen further that the additional operation of stitching successive layers together does not slow up the normal operation of winding and forming paper pulp tubes.

It is to be understood that although a tube has been described in explaining the machine the invention is not limited to tubes, but the machine may be adapted to operate upon other types of compacted bodies formed of a plurality of layers of fibrous pulp. 1

The expression paper pulp appearing in the specification and claim is not intended as a limiting expression as it is is adapted to use any type of fibrous pulp whether it is strictly paper pulp or not.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

I claim:

A machine for forming tubes from fibrous pulp or other fibrous material comprising means for feeding pulp in a thin sheet, a mandrel adapted to receive the sheet of pulp, means for rotating said mandrel to wind the sheet into a tube having a plurality of layers, means for pressing each succeeding layer against a preceding layer, a stitching roller adjacent said mandrel provided with a multitude of spaced projections, and means for forcing said stitching roller against the tube while it is being formed, said projections being arranged to force each succeeding layer into a preceding layer at a multitude of spaced points to produce the effect of stitching after the succeeding layer has been pressed against the preceding layer.

RUDOLPH H. VON LIEDTKE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 549,999 Fairbanks et a1. Nov. 19, 1895 1,037,671 Seigle Sept. 3, 1912 1,465,177 Richter Aug. 14, "1923 1,854,230 Schur Apr. 19, 1932 1,864,674 Schur June 28, 1932 1,957,732 v Rowe May 8, 1934 2,106,246 Fourness Jan. 25, 1938 2,186,771 1940 Smith Jan. 9,

obvious that the machine 

